1. Field of the Invention
The invention relates, in a general manner, to touch-sensitive control interfaces, and relates more particularly to helping the operating of such control interfaces. One particularly worthwhile application of the invention relates to the use of touch-sensitive control interfaces in the aviation field. However, the invention also applies to any other field in which touch-sensitive interfaces are used in an environment subject to vibrations or, in a general manner, to disruptions that are likely to hamper the user and increase the risks of operating errors.
2. Description of the Relevant Art
When actuating a control button, the hand of the user may be subjected to shakings or to errors of appreciating the position of the zone to be actuated. This problem is posed more acutely when the arm of the operator is stretched out so that, in all cases, it is necessary for the user to hold his gaze on the zone to be operated while his attention must remain concentrated on another task.
These problems or ergonomics are also posed in an acute manner when it involves carrying out relatively long tasks in an environment subject to vibrations or to disruptions, such that, with fatigue in addition, the operator in the long run experiences difficulties in perfectly positioning his fingers on a zone of the interface to be operated.
Furthermore, although the mechanical interfaces, of the control button type, make it easy to identify the position of a member to be operated, notably by allowing the user to rest his finger on a member that can be identified by touch, the development of the touch-sensitive interfaces does not make it possible to identify by touch a control zone to be operated.
Moreover, when they are no longer perfectly clean, the touch-sensitive interfaces are likely to become slippery.
In view of the foregoing, it has been found that the touch-sensitive interfaces, although advantageous in several respects, are not very convenient to use in environments subject to vibrations or to turbulence of unforeseeable amplitudes. This is in particular the case on board aircraft in which, notably, the vibrations or air pockets prevent the pilot from accurately positioning his finger on a zone to be operated.
It has furthermore been found that the use of such interfaces requires, on the part of the user, in particular the pilot, holding his gaze on the interface while his attention should be maintained on another task, for example during landing, while the risks of error should be avoided.